1. Field of the Invention
The present invention relates to a tilt device for allowing a steering column to be tilted so that a driver can adjust the position of a steering wheel to conform to his/her figure in order to more comfortably drive a vehicle.
2. Background of the Related Art
In general, a tilt device comprises a mounting bracket fixed to a vehicle body, a tilt bracket connected to the mounting bracket and having a pair of side walls with tilt slots for guiding a tilt operation, a distance bracket fixed from below to the outer periphery of a steering tube which rotatably supports a steering shaft and having a pair of side walls with through holes, and a tilt-locking mechanism arranged through the tilt slots of the tilt bracket and the through holes of the distance bracket to cause tight contact between the side walls of the tilt bracket and the side walls of the distant bracket to lock a tilt of a steering column.
A conventional tilt device of the above structure is disclosed in U.S. Pat. No. 6,062,101. The above conventional tilt device has a tilt bracket of a laterally symmetric structure. When a tilt-locking mechanism is placed in a locking position, both right and left side walls of the tilt bracket are bent inward and closely contacted respectively with right and left side walls of a distance bracket to lock the distance bracket from vertical movement so that the tilt operation of a steering column is locked.
Therefore, the above conventional structure requires that the side walls of the tilt bracket should be elastically bent. As a result, there is a problem that the steering column has a weak supporting strength, in particular, in lateral directions.
In the meantime, U.S. Pat. No. 4,330,139 discloses a tilt device as shown in FIG. 1. Referring to FIG. 1, a steering bracket 1 integrally comprises a mounting bracket and a tilt bracket, in which a left side wall 2 has a flange or reinforcing portion 3. In such a structure, the left side wall 2 is not deformed but a right side wall 4 is deformed to perform a locking operation.
However, the above structure has a problem that fabrication is not simple since the steering bracket 1 has a complicated configuration. Further, as shown in FIG. 1, rear portions of the side walls 2 and 4 of the steering bracket 1 are connected to a connecting portion 5. As a result, during locking, the right side wall 4 is not uniformly deformed across its front and rear portions thereby obstructing reliable locking.